While this does not hold for our current Gregorian calendar, a discrepancy of 8 days would have been the case in the Julian calendar during the 14th century, resulting in Winter solstice falling on December 13. With the original adoption of the Gregorian calendar in the 16th century the discrepancy was 10 days and had increased to 11 days in the 18th century when Scandinavia adopted the new calendar, with Winter solstice falling on December 9.

It is said that she consorted with the Devil and that her children were invisible infernals. Thus the name may be associated with both lux (light) and Lucifer (Satan), and its origins are difficult to determine. The present custom appears to be a blend of traditions.